3-methylenephthalide-acrylonitrile interpolymers



United States Patent 3-METHYLENEPHTHALIDE-ACRYLONITRILE IN TERPOLYMERSHarry W. Coover, Jr., Joseph B. Dickey and Newton H. Shearer, Kingsport,Tenn., assignors to Eastman Kodak Company, Rochester, N. Y., acorporation of New Jersey No Drawing.

Serial No. 78,222, now Patent No. 2,618,627, dated November 18, 1952.Divided and this application August 25, 1952, Serial No. 306,312

4 Claims. (Cl. 26085.5)

This invention relates to polymers of 3-methylenephthalide and to aprocess for preparing them.

This application is a division of our application Serial No. 78,222,filed February 24, 1949, now U. S. Patent 2,618,627, dated November 18,1952.

3-methylenephthalide has the following formula:

and can be prepared by methods described by Gabriel, Berichte, vol. 17,page 2521 (1884) or Yale, Jour. Am. Chem. Soc., vol. 02, page 1547(1947). This compound can also be named3-methylene-1(3H)-isobenzot'uranone.

Gabriel noted that a residue, result of slight polymerization, wasobtained by his method of preparation. While Gabriel was only able toobtain a polymer of very low molecular weight, we have found thatpolymers of high molecular weight can be obtained from3-methylenephthalide, and we have further found that3-methylenephthalide readily lends itself to interpolymerization withother polymerizable compounds. "lhe polymers obtained according to ourinvention are characterized by their high melting points, and we havefurther found that these polymers can readily be dissolved in certainsolvents to give solutions which are useful in the preparation of films,fibers, sheets, etc.

It is, accordingly, an object of our invention to provide an improvedmethod for preparing polymers of 3-methylenephthalide of a highmolecular weight. it is a further object of our invention to provideinterpolymers of 3- methylenephthalide and a method for preparing them.A further object is to provide films, fibers, sheets, etc. prepared fromour new, high molecular weight polymers and means for obtaining suchmaterials. Other objects will become apparent from a consideration ofthe following description and examples.

According to our invention, we prepare polymers of 3-methylenephthalideof high molecular weight by subjecting 3-methylenephthalide or a mixtureof 3-methylenephthalide and of from 1 to 3 other polymerizable compoundsto the influence of a peroxide polymerization catalyst.

Typical peroxide polymerization catalysts include carboxylic acidperoxides, e. g. acetyl, propionyl, benzoyl, acetyl benzoyl, etc.peroxides, the alkali metal persulfates, e. g. sodium, potassium, etc.persulfates, ammonium persulfate, hydrogen peroxide, t-butyl peroxide,the alkali metal perborates, e. g. sodium perborate, etc., etc. The

amount of catalysts employed varies and generally is a function of thecompounds being polymerized. Usually from 0.01 to 3.0 percent by weight,based on the total weight of the materials being polymerized, issuificient, although larger amounts can be used when so desired.

The polymerization can be accelerated by heating the reaction mixture,if desired. For example, temperatures varying from room temperature(about 25 C.) to the reflux temperature of the reactants (usually about100 ,C.) can be advantageously employed. Temperatures Originalapplication February 24, 1949,

which apparently was the varying from 35 to 75 C. have been found to beespecially uselul in utilizing our invention.

The process or our invention can be carried out en masse, or thematerials to be polymerized can be dissolved in a suitable solvent andthe solution subjected to polymerizing conditions in the presence of atleast one of the catalysts set forth above. when volatile or low boilingsolvents are employed, the polymerization can be carried out undersuperatmospheric pressures. '1 ypical solvents or diluents includebenzene, toluene, xylehes, 1,4-dioxane, n-hexane, acetonitrile,glycolonitrile, etc. A solvent is advantageously selected which is alsoa solvent for the interpolymer, although solvents which dissolve themonomers being polymerized, but not the interpolymer formed, can beemployed. The polymers can be obtained from the solutions by pouring thesolution into a liquid in which the polymers are insoluble, e. g. water,methanol, acetic acid, etc., or the solvent can be evaporated on rromthe solution.

3-methyleneplllhal1ue can also be polymerized according to our inventionby a bead or emulsion method in whlch water or some other medium inwhich S-metnylenephthalide alone (or mixtures of 3-methylenephthalideand from 1 to 3 other polymerizable compounds) is insoluble, is employedas a dispersing medium, with or without emulsllylng agents (e. g. soap,starch, polyvinyl alcohol, gum arable, elc. Bead or emulsion methods, aswell as solution methods, oner the advantage that a more uniformpolymerization can be erlected, and these methods largely or entirelyavoid any external heating. Atter polymerization has been efiected, theemulsions can be broken by the addition of methanol, acetic acid, etc.

in the preparation of interpolymers from B-methylphthalide generally anyratio or the B-methylenephthahde to the total polymerizaole compoundspresent can be used. We have found that polymers of particular utilitycan be obtained by subjecting a reaction mixture containing from 5 to 55percent or .t-methylenephthalide by weight, based on the total weight ofpolymerizable compounds present, to the action of one of the catalystsset forth above. The remaining 5 to percent by weight of polymerizablecompounds is advantageously composed of from 1 to 3 polylnerizablecompounds other than 3- melhylenephthalide. Such compounds includepolymerizable organic compounds containing a non-aromatic or cyclic (,=Cgroup. Compounds wherein at least two of the valences of the carbonatoms in the above group are satisfied by hydrogen atoms, e. g.compounds containing a CH2=C or a CH2=CH- group have been found to beespecially useful in our invention. Compounds usetul in preparinginterpolymers according to our invention include, for example,acrylates, G-meth' acrylates, fumarates, maleates, maleic anhydride,acrylonitrile, lat-substituted acrylonitrile, acrylamides, vinylsulfones, vinyl sulfonamides, alkenyl ketones, vinyl halides, vinylidenehalides, polyhalogehoethylenes (e. g. tetrafluoroethylene), hydrocarbonscontaining olefinic unsaturation, etc.

The acrylates or a-methacrylates we can advantageously use in ourinvention can be represented by the following general formula:

wherein R represents a member selected from the group consisting of ahydrogen atom, a methyl group and an acyloxy group, such as acetoxy,propionoxy, n-butyroxy, isobutyroxy, etc. groups (e. g. an acyl group ofan aliphatic carboxylic acid having 2 to 4 carbon atoms), and R1represents a member selected from the group consisting of a hydrogenatom, an alkyl group, such as methyl, ethyl, n-propyl, isopropyl,n-butyl, isobutyl, secondary and tertiary butyl, etc. groups (e. g. analkyl group represented by the formula CnH2n+1 wherein n represents apositive integer from 1 to 4), an aralkyl group, such as benzyl,fl-phenylethyl, etc. groups, or an alkenyl group, such as vinyl, allyl,fl-methallyl, crotyl, isopropenyl, etc. groups (e. g. an alkenyl grouprepresented by the formula CnHln-l. wherein n represents a positiveinteger isopropyl fumarate,

.butyroxyacrylate, etc.

The olefinic nitriles with ,which 3-rnethylenephthalide can beinterpolmerized can advantageously be represented by the followinggeneral; formula:

CH I -QE R2 wherein R2 representsa member selected from the groupconsisting of a hydrogenatom, a; methyl group, or an acyloxy group,fsuchas ,acetoxy, propionoxy, n-butyroxy, isobutyroxy,. etc. groups (e. g. anacyl group of an aliphatic carboxylic acid having 2 to 4'ca rbon atoms).Typical are acrylonitrile, m-methacrylonitrile, ;u-aceto1y c y i r lc 11bu yr xya y uit l t The olefinic ketones whiehwe can advantageously use.inour invention canbe-represented by thefollowing general formula:

i REC-B4 wherein Rs represents a member selected from. thegroupconsisting of an alkyl -group, such as-methyl, ethyl,'- npropyl,isopropyl, n-butyL-isobutyLi etc. groups '(e. g. an alkyl group of theformula-'CnI-lzn- -whereinnrepresents a positive integer from 1 to 4)andanalkenyl group, such as vinyl, B-rnethallyl, isopropenyl, -crotyl,.etc. groups (e. g. an alkenyl group of the formula CnH2n-1 wherein nrepresents apositive integer from-'2 to ,4), and R4 representsan-alkenyl group, .suchas vinyl, allyl, ',8-

"methallyl, isopropenyl, crotyl, etc. groups (eh-g. an alkenyl group ofthe-formula cnHzn-rwherein n represents a .positive integer from-2 to4). Typical are-methyl isopropenyl ketone, methyl vinyl ketone, 'ketone,ethyl isopropenyl-=ketone, divinyl ketone 'diisopropenyl ketone, diallylketone, etc.

n-butyl vinyl The olefinic acrylamides whichwecan-advantageously use canbe represented by the following-general formula:

'-wherein R5 represents a member selected fromthe group consisting ofahydrogen atom, a methyl groupand an acyloxy group, such as- -acetoxy,propionoxy, n-butyroxy, isobutyroxy, etc. groups (e.. g. an acyl groupofa carboxylic acid having-2-to 4 carbon atoms). Typicalare acrylamide,a-methacrylamide, -a-acetoxyacrylamide, etc.

'The maleates or fumarates whichwecanexpeditiously use can berepresented by the followinggeneral formula:

.wherein R and R7 each represents a member selected from the'groupconsisting of a hydrogen atom, an falkyl group, such as methyl, ethyl,n-propyl, isopropyl, n-butyl, isobutyl, etc. groups (e. g. an alkylgroup having the formula C7LH21L+1 wherein nis-a positive integer from 1to 4), an aralkyl group, such as benzyl, fi-phenylethyl, :etc. groups,and an alkenyl group, such as vinyl, allyl, S-methallyl, crotyl, etc.groupsv (e. ghan alkenyl group of the formula CitH2n1 whereinz-nrepresents .a postive integer from 2' to 4). Typical'are maleicacid,monomethyl maleate, monomethyl 'fumarate, dimethyl .maleate, dimethylfumarate, diethyl maleate,..diethyl fumarate, din-propylmaleate,'di-n-fumarate, diisopropylmaleate, didi-n-butyl maleate,di-n-butylfumarate, diisobutyl maleate, 'diisobutyl fumarate, dibenzylmaleate, dibenzyl fumarate, diallyl maleate, etc.

The olefinic -carboxylic acid esters which we can; advantageously usecan be represented bythe} following general formula:

-vinyl bromide, vinyl fluoride, -isopropenyl chloride,

wherein R3 represents a member selected from the group consisting ofahydrogen atom, an alkyl group, such as methyl, ethyl, n-propyl,isopropyl, etc. groups (e. g. an alkyl group of the formula CnH2n+1wherein n represents a positive integer from 1 to 3), an aryl group,such as phenyl, 0-, mand p-methylphenyl, etc. groups (e. g. amononuclear aryl group of the benzene series having 6 to 10 carbonatoms),,and.a substituted aryl group, such as chlorophenyl,carbovinyloxyphenyl, i. e.

ll C.OCH=GH1 -et :.-groups. wTypical arervinyl formate, vinyl acetate,

vinyl propionate, vinyl n-bu-tyrate, vinyl. i'sobutyrate, vinylbenzoate, vinylchlorobenzoate, divinylphthalate, etc.

The olefinichydrocarbons with which we can interpolymerize3.-methylenephthalide can be represented by the following generalfformula:

' R -CHE H wherein R9 represents a memberselectedfrorn the groupconsistingpf h o .a em me y to a 'y group, such as phenyl, o-, mandp-chlorophenyl, dichlorophenyl, p-acetaminophenyl, etc. groups, a vinyl(ethenyl) group (CHz==CH?) and a substituted ethenyl group. Typical areethylene, propylene, styrene, o-, mand p-chlorostyrene,p-acetaminostyrene, 1,3-butadiene, 2,3-dimethylbutadienel,3,chl0roprene,piperylene, etc.

The olefinic or vinylsulfonamides which can advantageously be used inour process can be represented by th ascnera t nm la wherein Rm-and R11each represents a .member selected from the group consisting ofahydrogenhatom and.,-.an alkyl group, such as methyl, i ethyl,.n-propyl, .uisopropyl,

-n-butyl,etc. groups (e. .g. an alkyl group ofutheformula CTLH2n+Lwherein in represents a positive integer from :1 .to 4), andR12.representslamember. selected from the group consisting of a hydrogenatom,-a methyl groupand can ethyl group. Typical arevinylsulfonamide,-Nrn1ethyl vinylv sulfonarnide, N-n-butylisopropenylsulfonamide,etc.

The vinyl halides which we can advantageously use can be representedbythe following general formula:

a methyl group and a halogen atom such as chlorine, bromine, iodine, orfluorine. Typicalarevinyl chloride,

vinylidene-chloride, :vinylidene' bromide, -vinylidene -fluoride, etc.

Other polymerizable compounds not embracedrby the above formulas whicheanadvantageously be utilized in "our invention includemaleic-anhydride, itaconic anhy- 'dride, N-vinylphthalimide,N-vinylmaleimide, -vinylpyridine, chlorotrifluoroethylene, l,l-dichloro-2,2-difluoroethylene, tetrafluoroethylene,Z-methoxybutadiene'dfi,

; etc.

Certainv so-calledactivating-agents canbe used .in conjunctionwrth theperoxide polymerization catalysts, if desired. Such agents include, "forexample, sodium bisulfite, ferrous sulfate, etc. :Chain; lengthregulators, e.: g.

dodecyl mercaptan, etc.,- canalso beused, ifdesired.

' The following examples" will. serve to illustrate further .the mannerwhereby rwe practice our invention. Exgmple1.+-Poly-3-methylenephthirlide-solution method for Z8hours at"40 C. Theresulting white polymer wasobtained as a swollen mass, which wasfoundto-be soluble in a 50/50 m ixture of acetonitrile anddimethylformagtide. The dried polymer had a melting point of 320 t-nutylperoxide also was satisfactory for the polymerization, although slightlynig..er temperatures, e. g. 60- 80 C. had to be used.

Example 2.-1merp0lymer of styrene and 3-methylenephthalide 9 g. ofstyrene, 1 g. of 3-methylenephthalide, and 0.02 g. or benzoyi peroxidewere placed in a flask, and the air in the flash was replaced withgaseous nitrogen. The 1138K was then heateu on a water oath at 60 C.until its contents had set to a clear, hard mass. The polymer dissolvedin chlorobenzene and had a softening point of 150 C. it was found to bereadily adaptable for molding purposes.

A molecularly equivalent amount of 2,5-dichlorostyrene can be used inplace of the styrene in the above example. The resulting product isobtained in the form of a clear, hard mass.

Example 3.Ply-3-methylenephthalide.-Bulk method 10 g. of3-methylenephthalied and 0.01 g. of benzoyl peroxide were heatedtogether in a flask for 12 hours at 65-70 C. The hard mass obtained hada softening point of 300 C. and was soluble in N,N-dimethylacetamide.

Example 4.Interpolymer of acrylonitrile and 3-methylenephthalide g. ofacrylonitrile, 5 g. of 3-methylenephthalide, and 0.01 g. of acetylperoxide were heated together in a glass bottle for 12 hours at 60 C.The white, powdery polymer had a softening point of 180 C. and wassoluble in dimethylformamide.

The softening point of interpolymers of acrylonitrile and3-methylenephthalide can be varied by regulating the ratio ofacrylonitrile to S-methylenephthalide. Generally the higher thepercentage of 3-methylenephthalide, the higher the melting point of theinterpolymer.

Example 5.P0ly-3-methylenephthalide.Emulsi0n method had a softeningpoint of 310 C. and was soluble in dimehtylformamide.

Example 6.lnterpolymer of styrene and 3-methylenephthalide 5 g. ofstyrene and 5 g. of 3-methylenephthalide were placed in a flask whichcontained 0.02 g. of benzoyl peroxide, and the air in the flask wasreplaced by gaseous nitrogen. The flask was then heated at 100 C. for 48hours on a water bath. The clear, hard mass had a softening point of 252C. and contained 76 percent by weight of 3-methylenephthalide.

The amount of 3-methylenephthalide in the polymer can be controlled byadding the 3-methylenethalide to the reaction mixture during the courseof the polymerization at a rate approximating the rate it is used up.This might be desirable where a polymer having a softening pointsutficiently low tor molding purposes is desired. The presence of largeamounts of 3-rnethylenephthalide in the reaction mixture at any one timetends to produce a polymer of an unusually high melting point.

Example 7.Interp0lymer of acrylonitrile and 3-methylenephthalide 8 g. of3-methylenephthalide and 2 g. of acrylonitrile were suspended 100 cc. ofacetic acid to which 0.1 g. of acetyl peroxide had been added. Thereaction mixture was then heated on a water bath for 24 hours at 60 C.The white polymer which was thus obtained had a melting point of 295 C.and was soluble in N,N-dimethylacetamide.

lnterpolymers of 3-methylenephthalide and acrylonitrile containing about70 percent by weight of acrylonitrile are useful in the preparation ofsynthetic fibers. The fibers can readily be prepared by dissolving theinterpolymer in dimethylformamide or N,N-dimethylacetamide and forcingthe solution under pressure through a spinneret into a coagulating bath.The fibers can be stretched 200-800 percent to increase their strength.

Example 8.Interp0lymer of acrylonitrile and3-methylenephthalide.-Emulsi0n method Example 9.Interp0lymer of3-methylenephthalide and methyl a-methacrylate 9 g. of3-methylenephthalide, 1 g. of methyl a-methacrylate and 0.2 g. ofbenzoyl peroxide were dissolved in 25 cc. of acetonitrile. The solutionwas then heated on a water bath at 70 C. for 48 hours. The precipitatedwhite polymer was obtained in almost theoretical yield.

Example 10.-Interp0lymer of 3-methylenephthalide and 2,5-dichlorostyrene9 g. of 2,5-dichlorostyrene, 1 g. of 3-methylenephthalide and 0.3 g. ofacetyl peroxide were heated at 60 C. for 48 hours. At the end of thistime the mixture had set to a hard mass having a high softening point.It was found to be useful for molding purposes.

Example 11.-Interp0lymer of 3-methylenephthalide and vinylidene chloride5 g. of 3-methylenephthalide, 5 g. of vinylidene chloride, 2 g. ofcommercial soap flakes, 0.1 g. of ammonium persulfate and 0.2 g. ofammonium bisulfite were added to cc. of distilled water in a pressurebottle after heating the closed bottle for 20 hours at 40 C., aceticacid was added, and the precipitated polymer was filtered, washed andthen dried. The polymer had a softening point above C.

When a molecularly equivalent amount of vinyl chloride replaces thevinylidene chloride in the above example, a clear, hard polymer having ahigh softening point can be obtained.

By substituting molecularly equivalent amounts of other polymerizablecompounds for those illustrated in the examples, other interpolymersexhibiting valuable molding, fiberand film-forming properties can beobtained. Many of the polymers of our invention, e. g. interpolymers ofstyrene and 3-methylenephthalide, are useful in the preparation ofelectrical insulating materials. The properties of the polymers can bevaried during or after polymerization by incorporating therein certainplasticizing agents, e. g., di-n-butyl phthalate, camphor, di-n-butylsebacate, di-p-ethoxyethyl succinate, triacetin, etc. Fillers, coloringmatter, etc. can also be :incorporated in the polymers. Adhesivematerials can 'be prepared by interrupting the polymerization before thepolymer has set to a hard mass and while the polymer is still in aviscous or gummy state.

What we claim as our invention and desire secured by Letters Patent ofthe United States is:

A resinous two-component interpolymer of 3- methylenephthalide andacrylonitrile, said interpolymer containing from 5 to 95 per cent byweight of 3-methylenephthalide and from 95 to 5% by weight ofacrylonitrile in the polymer molecule.

2. A resinous two-component interpolymer of 3- rnethylenephthalide andacrylonitrile. said interpolymer containing 80 per cent by weight of3-methylenephthalide and 20% by weight of acrylonitrile in the polymermolecule.

3. A resinous two-component interpolymer of 3- methlenephthalide andacrylonitrile, said interpolymer containing 50 per cent by weight of3-rnethy1enephthalide and 50% by weight of acrylonitrile in the polymermolecule.

1. A RESINOUS TWO-COMPONENT INTERPOLYMER OF 3METHYLENEPHTHALIDE ANDACRYLONITRILE, SAID INTERPOLYMER CONTAINING FROM 5 TO 95 PER CENT BYWEIGHT OF 3-METHYLENEPHTHALIDE AND FROM 95 TO 5% BY WEIGHT OFACRYLONITRILE IN THE POLYMER MOLECULE.